Gallium oxide substrate division method

Abstract

To divide a β-type gallium oxide substrate having a (001) plane as a main surface satisfactorily. A method of diving a gallium oxide substrate includes: a step of forming a plurality of dividing grooves along the extending direction of the (100) plane of a β-type gallium oxide substrate having the (001) plane as the main surface; a step of processing the β-type gallium oxide substrate into strips by cutting the substrate in a direction perpendicular to the extending direction of the dividing grooves; and a step of cleaving the strip-shaped β-type gallium oxide substrates 10 along the dividing grooves for singulation. Since the plurality of dividing grooves are thus formed along the cleavage planes, the substrate can be divided satisfactorily without causing flaky peeling on the cleavage surfaces by cleaving the substrate along the dividing grooves.

1 . A method of dividing a β-type gallium oxide substrate, the method comprising:
 a step of forming a plurality of first dividing grooves along an extending direction of a (100) plane of a β-type gallium oxide substrate having the (001) plane as a main surface; 
 a step of processing the β-type gallium oxide substrate into strips by cutting the β-type gallium oxide substrate in a direction perpendicular to an extending direction of the first dividing grooves; and 
 a step of cleaving the strip-shaped β-type gallium oxide substrates along the first dividing grooves for singulation. 
 
     
     
         2 . The method of dividing a β-type gallium oxide substrate as claimed in  claim 1 , wherein the first dividing grooves are formed by etching. 
     
     
         3 . The method of dividing a β-type gallium oxide substrate as claimed in  claim 1 , wherein the first dividing grooves are formed on a back surface located on a side opposite to an element forming surface. 
     
     
         4 . The method of dividing a β-type gallium oxide substrate as claimed in  claim 3 , further comprising a step of forming a plurality of second dividing grooves in the element forming surface along the extending direction of the (100) plane,
 wherein a straight line connecting the first and second dividing grooves have an angle of about 76° with respect to the element forming surface. 
 
     
     
         5 . The method of dividing a β-type gallium oxide substrate as claimed in  claim 2 , wherein the first dividing grooves are formed on a back surface located on a side opposite to an element forming surface.